OXFORD , Mississippi -LRB- CNN -RRB- -- Unraveling the complex back stories of the more than 200 pardons issued by former Mississippi Gov. Haley Barbour is revealing serious questions about how pardon review decisions were carried out .

But perhaps no pardon is as confounding as the case of Harry Bostick . The retired Internal Revenue Service investigator 's pardon has been called `` heinous '' by critics of Barbour .

`` Someone did n't do their homework on this case , '' said Democratic state Rep. Steve Holland .

When Barbour pardoned Bostick in January , the convicted DUI felon was sitting in an Oxford , Mississippi , jail cell for violating the terms of a previous DUI sentence and was awaiting formal charges from yet another drunken driving accident in October that ended in the tragic death of 18-year-old Charity Smith . Who 's at fault in that accident has yet to be determined .

The teenage girl from Okolona , Mississippi , had big dreams of saving money and going to college to pursue a business degree . The young woman 's death and the controversy surrounding the case have devastated Linda Smith , Charity 's mother .

`` She should still be here with me . She should still be here with me . This should not have happened , '' Linda Smith told CNN during an emotional two-hour interview .

Bostick was given a full pardon for a felony drunken driving offense dating from March 2009 . That offense was Bostick 's third drunken driving arrest in a little more than year .

The Mississippi Parole Board and Barbour have issued statements saying they did n't know Bostick had another DUI arrest in October . It came after his pardon case had already been reviewed .

Oxford Police Sgt. Hildon Sessums arrested Bostick twice over a span of a year for DUI .

`` Right before I put the cuffs on him he said , ` Do n't do this to me . ' And my comment to that usually is , you did it to yourself , '' Sessums told CNN as he recounted details of the two arrests .

For the third DUI , Bostick had been sentenced in March 2010 to a year of house arrest and four years in Mississippi 's drug court program , an intense drug-and-alcohol-abuse treatment program with strict guidelines that convicted felons like Bostick must follow .

Bostick was still going through the drug court program when he started applying for a pardon last summer . High-profile friends wrote letters to Barbour touting what they called Bostick 's genuine lifestyle change .

The letters detail what friends described as Bostick 's slide into alcoholism after the tragic death of his teenage son in a `` freakish house fire '' and after Bostick 's divorce , according to pardon and parole documents obtained by CNN .

One letter said Bostick `` no longer drinks alcohol '' and `` has turned his life around . ''

`` Harry Bostick has led a tragic life . A life that has now been turned around by a grace that is bigger than him . He can now be a positive factor in many lives , '' wrote retired U.S. attorney Jim Greenlee .

On September 30 , the Mississippi Parole Board sent its review of the Bostick case to Barbour . The board recommended Bostick for a full pardon with a divided 3-2 vote .

About a week later , on October 7 , Bostick was driving under the influence again , according to the Mississippi Highway Patrol . Charity Smith attempted to pull out onto a highway just outside Tupelo when Bostick 's truck slammed into the side of her car .

Charity Smith was killed and her older sister suffered serious injuries .

Bostick still has not been indicted by a grand jury in that crash . Because his third DUI was pardoned , a conviction in the latest DUI case would technically be his third offense , but that would still make it a felony in Mississippi .

The Mississippi Parole Board and Barbour are at a loss to explain how Bostick 's pardon could have unfolded the way it did . State officials say there is not a mechanism in place to alert them of situations like this .

A Department of Corrections spokeswoman referred all questions about the case to the Mississippi Parole Board .

Bosticks ' pardon application packet sent from the Parole Board to the governor 's office is filled with references to the `` expedited investigation into the circumstances surrounding Bostick 's crime , '' meaning his third DUI from 2009 .

According to a state prison official , the `` expedited '' rush was a result of a flood of pardon applications as the clock was counting down toward the end of Haley Barbour 's final term as governor .

Barbour refused CNN 's request for an interview but his spokeswoman , Laura Hipp , issued a statement .

`` In reviewing Mr. Bostick 's case , Gov. Barbour took the Parole Board 's recommendation into consideration , and he was n't aware of the subsequent charges , '' she said .

Shannon Warnock , chairwoman of the Mississippi Parole Board , issued a statement saying : `` I can say that Mr. Bostick 's application was supported by testimonials from trustworthy and outstanding members of the community . While the reported circumstances of that arrest are troubling , our system of justice does regard everyone as innocent until proved guilty . ''

Linda Smith , Charity 's mother , worries her teenage daughter 's death has been forgotten in all of this . She struggles to understand how state officials could not have known that the man involved in her daughter 's violent crash was the same Harry Bostick who had petitioned for a pardon .

`` She was a person . She was n't just some name on a piece of paper . A beautiful person , '' said Linda Smith .

Her days now are often spent weeping over her daughter 's death .

She cried throughout most of her interview with CNN as she showed photographs of the beautiful girl with big dreams .

Linda Smith described her daughter as an artist with a big heart , and she proudly talked about the powerful emotions she feels holding a collection of her daughter 's paintings .

One of the paintings was a gift from Charity Smith to her mother . Instead of signing the painting , Charity left her handprint on the back .

But perhaps the most poignant painting was of swirling blues and purples and oranges that reads `` Life is Short . ''

The girl with the artist 's heart is now mourned by her mother with a broken heart .

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Harry Bostick is a repeat DUI offender

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He was pardoned for his third DUI while facing charges for a fourth

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Bostick received one of more than 200 pardons issued by Mississippi 's former governor

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Former Gov. Haley Barbour says he was n't aware of Bostick 's fourth DUI violation